1. Field of the Invention
The present invention relates to a stereoscopic display unit for performing three-dimensional display by using binocular parallax.
2. Description of the Related Art
In the past, stereoscopic display units that realize stereoscopic vision by providing different images (parallax images) as a viewer left-eye image and a viewer right-eye image between which parallax exists. Examples of methods of such stereoscopic display units include eyeglass method and naked eye method. The eyeglass method realizes stereoscopic vision by wearing special eyeglasses for stereoscopic vision. In Japanese Patent No. 3767962, as eyeglasses for stereoscopic vision, a method using a polarization filter is disclosed.
Meanwhile, in the naked eye method, stereoscopic vision is enabled with naked eyes without wearing the special eyeglasses. Examples of naked eye methods include parallax barrier method and lenticular method. In the parallax barrier method, a structure called a parallax barrier as a parallax separation means is arranged oppositely to a two-dimensional display panel. Right and left parallax images displayed on the two-dimensional display panel are parallax-separated in the horizontal direction by the parallax barrier, and therefore stereoscopic vision is realized. In the lenticular method, a lenticular lens as a parallax separation means is arranged oppositely to a two-dimensional display panel. Right and left parallax images displayed on the two-dimensional display panel are parallax-separated in the horizontal direction by the lenticular lens, and therefore stereoscopic vision is realized. Further, a display unit in which display is changeable between two-dimensional display and three-dimensional display by the lenticular method by using a variable lenticular lens composed of a liquid crystal lens or a liquid lens has been known (refer to Japanese Unexamined Patent Application Publication No. 2000-102038 and Japanese Unexamined Patent Application Publication No. 2005-517991).